228 



localities of the sparry iron ore, and they place the principal deposits 

 of the mineral on the confines of the secondary system. 



In confirmation of their views they describe sections on the south 

 side of the central axis, especially in the neighbourhood of Bleiberg, 

 where they state that the secondary system is immediately underlaid 

 by grauwacke-slate, containing calcareous beds with many organic 

 remains, chiefly composed of encrinital stems and shells of thefollowing 

 genera, viz. Producta, Terebratula and Pecten. Two or three of these 

 shells have been identified with species characterizing the English 

 mountain limestone. They therefore conclude from the evidence of 

 organic remains, as well as from mineralogical characters, that in this 

 part of the eastern Alps there is a zone of true transition rocks, inter- 

 posed between the primary and the secondary series. 



3. Red and variegated sandstone, gypseous marls, and conglomerates ; 

 sometimes with subordinate beds and masses of fetid limestone, rauch- 

 wacke, &c. %c. — It is stated that this formation is found nearly through 

 the whole extent of the Austrian Alps, overlying the transition series, 

 and forming the base of the precipices of older Alpine limestone. A 

 detailed section, south of Werfen, exposes beds of red conglomerate, 

 sandstone, and red gypseous marls, not to be distinguished minera- 

 logically from the new red sandstone of England. Other sections in 

 the valley of Bleiberg in Carinthia, and on the north side of the 

 Erzberg, exhibit similar deposits of red sandstone and gypseous marls, 

 separating the grauwacke, with the organic remains abovementioned, 

 from the Alpine limestone ; they are accompanied by great dislocations, 

 and the appearance of masses of dark-coloured augitic trap and of trap 

 breccia. Subordinate to the red sandstone series between Haring, Soil 

 and Schwatz, are many masses of limestone of very varied structure. 

 Some of them are compact, some white and crystalline, some yellow 

 and earthy, and some cavernous. The greatest number of them are 

 magnesian, and some of them bituminous and fetid. These masses of 

 limestone were formerly considered as transition. As, however, these 

 different varieties of limestone appear to be subordinate to the red 

 sandstone, they are placed by the authors in the secondary system, 

 and are compared with the beds of magnesian limestone, which in so 

 many parts of Europe are subordinate to the great group of the new 

 red sandstone. 



The rocks above described are immediately surmounted by the 

 Alpine limestone, under which term are included the two great se- 

 condary calcareous zones of the Alps overlying the red sandstone 

 groups. This enormous deposit is subdivided into older Alpine lime- 

 stone, limestone with subordinate saliferous marls, &c, and younger 

 Alpine limestone. 



4. Older Alpine limestone. — Near Bleiberg the red standstone 

 group is surmounted by a thinly bedded fetid limestone, which forms 

 the base of, and appears to pass into the lower portion of the older 

 Alpine limestone. A detailed section of the beds forming the base of 

 the northern calcareous zone near Werfen, brings the two zones un- 

 der comparison. It is shown that the thin-bedded bituminous lime- 

 stone is sometimes so much expanded (e. g, at Seefeld) as to occupy 



